upload asset obtained from AssetsLibrary to server - objective c

I'm currently writing a program to upload video files from iphone photo album to server. I'm able to obtain the Asset from the library but how do I convert it to byte array. I already know how to upload file from application folder using NSStream. i'm juz puzzled how do up you upload asset to the server? do I convert it to nsdata? or there other approach. Would greatly appreciate any开发者_如何转开发 help. Thanks

I am guessing that your server is expecting multipart form data, have a look at these answers:

File Upload to HTTP server in iphone programming